The present invention relates to a system for correcting a shift of the ignition timing occurring in the ignition device used with internal combustion engines.
In recent years ignition devices used with motor vehicles have required an increase in their output energy and have required improved accuracy and stability of the ignition timing in view of the purification of the exhaust gases from motor vehicles. Under these circumstances, ignition devices of the conventional contact breaker type are increasingly replaced by those of the fully transistorized type without contact breakers.
In this fully transistorized type of ignition device, the ignition timing signal is provided by a contactless signal generator such as an electromagnetic coil generator, an integrated circuit Hall generator or the like, but such a generator is disposed within a mating distributor which is, in turn, usually driven by a crankshaft connected to an associated internal combustion engine through a timing belt or the like. Even in fully transistorized ignition devices, therefore, a shift of the ignition timing due to ageing in the distributor driving system is increased with time. This shift of the ignition timing appears as a shift of the ignition timing developed, for example, during the idling of the engine and has greatly affected the output from the engines and the ingredients of the exhaust gases from the engines.
Therefore, the shift of the ignition timing is undersirable in view of measures to counter the exhaust gas emissions from internal combustion engines. Thus, it is desirable to correct a shift of the ignition timing of internal combustion engines and particularly during the warm-up thereof by some measure.